An adult human skeleton includes two hundred and six bones. During a lifetime a human may fracture one or more of these bones. Some fractures may be treated using a casting process. Certain other fractures of long bones may be treated using an intramedullary rod. For example, fractures of the ulnae, radii, humeri, femora, tibiae, and fibulae can be treated using an intramedullary rod. In such cases, the intramedullary rod can be permanently installed within these bones and the bone can be allowed to heal around the intramedullary rod.
Sometimes, these fractures can also result in a loss of bone, e.g., a bone gap, and it may be necessary to fill the bone gap with something to promote new bone growth. It can be advantageous to deliver a therapeutic agent to an area of a bone gap in addition to installing an intramedullary rod.